Which of the following problems is typically not a concern for single-layer push truck stockpiles?

When evaluating the different concerns associated with single-layer push truck stockpiles, degradation is typically not a significant issue. In a single-layer configuration, the material is often spread evenly and is more stable, which reduces the likelihood of particle breakdown that can occur with excessive handling or compaction in stacked layers.

On the other hand, segregation, contamination, and density are more prominent issues with such stockpiles. Segregation can happen if materials with different sizes or weights separate due to movement. Contamination is a concern as the stockpile may come into contact with foreign materials or debris. Density matters as it affects the compaction and overall quality of the aggregate mix. Therefore, while all of these factors are important to consider in aggregate handling, degradation is less likely to cause significant problems in a single-layer push truck stockpile setting.